Water-cooled grinding wheel



May 17, 1949. J. A. HARRlNG TON 2,470,350

nun cooLEn GRINDING mm.

Filed um ch 29. 1948 Patented May 17, 1949 UNITED STATES PATENT OFFICE WATER-COOLED GRINDING WHEEL Application March 29, 1948, Serial No. 17,765

1 Claim. 1

My invention relates to grinding wheels and, more particularly, to improved means for effecting internal cooling of the wheel and the work during operation of the wheel.

The primary object of my present invention is to effect the cooling of a grinding wheel by percolation of a liquid coolant radially of the wheel through the pores of the body thereof throughout its entire circumference.

Another important object of my invention is the provision of a novel grinding wheel assembly wherein liquid coolant introduced into the porous body of the wheel, radially inwardly of its periphery, will be concentrated at the periphery primarily adjacent the opposed leading edges thereof.

The invention is particularly advantageous in precision grinding work, wherein the reduced temperature of the wheel, and the elimination of dust, chips, and sparks, are particularlydesirable.

The above and still further objects of my invention will become apparent from the following detailed specification, appended claim, and attached drawings.

Referring with greater particularity to the drawings, wherein like characters indicate like parts throughout the several views:

Fig. 1 is a side elevation of my novel grinding wheel construction, some parts being broken away; and

Fig. 2 is a vertical axial section, taken substantially on the line 22 of Fig. 1.

Referring with greater particularity to the drawings, the numeral I indicates a conventional cutting wheel composed of any well-known abrasive substance, having any desired grain size, and a suitable bonding substance of any wellknown kind, and having a. porous homogeneous body. Wheel I, as shown, is formed with a metallic annular core 2, which is concentric with the periphery of the wheel I and defines an opening I at the center thereof.

For the purpose of securing the wheel I to a rotary shaft or spindle 4 having a tapered end portion 8, I provide a bushing 6 having a tapered openingwhich corresponds to the taper of the end I of shaft 4. The extreme outer end of the tapered portion 5 is provided with an axiallyextended stud I, which projects beyond the outer end of the bushing 6. The bushing 6 is held fast on the tapered portion-5 by means of a washerequipped nut 8 threaded on the stud I which engages an annular shoulder 9 on the bushing 6. The inner end portion of the bushing 6 is provided with a circumferential flange III which forms an abutment for the inner portion of an annular clamping flange II. A pair of radiallyprojectin-g cross-sectionally cylindrical keys I2, in the bushing 6, seat in keyways I3 in the annular clamping flange II to prevent relative rotation between the bushing t and the flange II. After the wheel I is positioned against the clamping plate II, as indicated in Fig. 2, a clamping flange I 4, identical in all respects to the clamping plate II, is placed against the outer face of the grinding wheel I and held against rotation with respect to the bushing by means of a pair of diametrically-opposed keys I5 seated in keyways I6 and I! in the bushing 6 and clamping flanges M respectively. The outer end of the bushing 6 is externally threaded, as indicated at I8, to receive an annular nut I9, which is provided with circumferentially-spaced spanner wrench-receiving openings 20.

The flanges II and I4 are formed to provide annular recesses 2i and have gripping contact with the sides of the grinding wheel I, only adjacent their peripheral edges, as indicated at 22. Each of the flanges II and I4 are further provided with a circumferentially-extended row of spaced apertures 23 which extend axially through and have their inner ends communicating with the annular recess 2 I. The outer side of each of the flanges II and I4 is provided with an annular lip 24 which inclines radially inwardly, as indicated at 25, to form an annular channel or trough 26 communicating with the spaced openings or apertures 23. The numeral 21 indicates a pair of conduits 21 which feed liquid coolant to the channels 26 from a source of supply, not shown.

As coolant is allowed to flow through the conduits 21, it flows into the channel 26 and through the apertures 23 to the annular recesses 2| between the flanges II and I4 and the grinding wheel I from whence it percolates into the porous body of the grinding wheel I. Centrifugal force. generated by rotation of the grinding wheel I and all parts associated therewith, causes the coolant to move radially outwardly through the pores or interstices of the grinding wheel I to the periphery thereof. Coolant, of course, will penetrate the entire body of the wheel I, but the greater portion will be concentrated at or near the sides thereof. Thus, the sides of the wheel I, which in certain grinding operations form the leading edges of relative movement between the grinding wheel I and the work piece to be ground and which require the greatest amount of coolant, will receive the same. I flnd that this arrangement not only maintains the grinding wheel at a low temperature and prevents undue wear upon the same, but also is an important factor in obtaining an accurate finish on the work piece.

My invention has been thoroughly tested and found to be entirely adequate for the accomplishment of the objectives as set forth; and, while I have shown a preferred embodiment of my invention, it will be obvious that the same is capable of modification without departure from the spirit and scope of the invention as defined by the claim.

What I claim is:

A grinding assembly including a rotary shaft having a tapered portion and a threaded end axially outwardly of said portion, a bushing having a tapered opening corresponding to the taper on said shaft and an axially outwardly opening recess at the smaller end of said tapered opening providing a shoulder, a nut engageable with said threaded portion and said shoulder to press said bushing on the tapered portion of said shaft, a radially outwardly-projecting circumferentially-extending flange integral with said bushing adjacent its inner end, a porous grinding wheel having an axially-extended central opening receivable on said bushing, a pair of axially-spaced annular clamping flanges axially slidable on said bushing one on each side of said grinding wheel, one of said clamping flanges abutting said iflange integral with said bushing, means positively locking said clamping flanges against rotation with respect to said bushing, said bushing having a threaded portion adjacent its outer end, a clamping nut on said threaded portion engageable with the other of said clamping flanges to move said clamping flanges and said grinding wheel toward frictional lockin engagement with each other and with the flange on said bushing, each of said clamping flanges being provided with a circumferentially-extended row of spaced apertures axially therethrough, said apertures being spaced uniformly from the axial center of said flanges and spaced radially inwardly from the periphery thereof, said flanges being provided with opposed annular recesses which extend radially from the central openings therein to a point beyond the spaced apertures, an annular lip carried by each of said flanges intermediate said rows of apertures and the peripheral edge of said flanges whereby to provide radially inwardly opening channels communicating with said apertures, and means for simultaneously supplying a fluid coolant to said channels radially outwardly of said bushing.

JOHN A. HARRINGTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 500,561 Carpenter et al July 4, 1893 533,958 King Feb. 12, 1895 796,466 Stolzenberg Aug. 8, 1905 2,378,070 Eastwood June 12, 1945 2,380,332 Scheer July 10, 1945 FOREIGN PATENTS Number Country Date 520,060 Great Britain Apr. 12, 1940 

